WO2001092830A1

WO2001092830A1 - Sensor device, setting device, reading device, and article administration system

Info

Publication number: WO2001092830A1
Application number: PCT/JP2001/004413
Authority: WO
Inventors: Shiro Kano
Original assignee: Yamatake Corporation
Priority date: 2000-05-30
Filing date: 2001-05-25
Publication date: 2001-12-06
Also published as: US6882273B2; AU2001258845A1; JP2001336956A; JP3579868B2; US20030107483A1

Abstract

A sensor device (2) comprising: a coil (20) for receiving an electromagnetic energy applied from the outside; a power source unit (21) for generating an internal power source from the electromagnetic energy; and a sensing circuit (24) having a sensor element mounted thereon. An allowable value, which is intrinsic to the sensor device and set by a setting/reading unit (1) on the basis of the output of the sensing circuit of the sensor device under a predetermined environment, is received and decoded and is stored in a nonvolatile memory (23). The sensor device under a measurement environment transmits the output and the allowable value of the sensing circuit to the setting/reading unit.

Description

Specification

Sensor device, setting device, readout device, and article management system

The present invention relates to a sensor device for detecting characteristics such as temperature and pressure, a setting device for setting the sensor device, and a reading device for reading information from the sensor device. The present invention relates to an article management system that manages articles using devices.

In temperature control such as air conditioning, an air conditioner or the like is drive-controlled in accordance with the result of determining whether or not the detected temperature is within an allowable temperature range, and a data collection device is generally used for this determination. For example, a data collection device includes a signal processing circuit having a temperature sensing element for detecting a temperature and an electronic circuit for converting the output of the device into an electric signal, and is connected to the signal processing circuit and analyzes the output of the circuit. And a controller. In general, the characteristics of the temperature-sensitive elements of the data collection device vary, and the output of the electronic circuit (the temperature detected by the temperature-sensitive elements) may not accurately indicate the actual temperature, which reduces measurement errors. Calibration is performed to

Conventionally, when performing this calibration, the signal processing circuit and the controller are connected by a cable, for example, and both are left in a constant temperature environment for a certain period of time, and then the temperature at which the output of the signal processing circuit is transmitted to the controller. Measurement is performed, and based on the relationship between the signal processing circuit output and the temperature obtained by performing such temperature measurement at multiple temperatures, the characteristics of the signal processing circuit are calibrated on the controller side, and the calibration result is sent to the controller. Saved. Prior to shipment of the data collection device, an allowable value (for example, an allowable temperature value) that defines an allowable range of parameters detected by the sensor device is set in the controller. When the data collection device is actually used, the controller corrects the output (detected value) of the signal processing circuit based on the calibration result, and compares the corrected detected value with the allowable value. Control is performed according to the result.

As described above, according to the conventional calibration method, it is necessary to configure a data collection device from a signal processing circuit and a controller that is paired with the signal processing circuit. Therefore, an arbitrary signal processing circuit and an arbitrary controller can be used. A data collection device cannot be configured in combination. In addition, since calibration is performed with the signal processing circuit and the controller physically connected, equipment such as a thermostatic chamber becomes large.

In recent years, data collection devices have been proposed in which a plurality of signal processing circuits each have a wireless function so that the output of the sensor element of each signal processing circuit is transmitted from the circuit to a controller. This proposed device has an advantage that a signal processing circuit can be attached to each of a large number of articles to appropriately detect the ambient temperature and the like of each article, but has the following problems.

First, the characteristics of the sensor device in the signal processing circuit, and consequently, the variation in the output of the electronic circuit

In order to reduce measurement errors caused by (individual differences), it is necessary to calibrate the characteristics of individual signal processing circuits.

Second, since it is necessary to store the calibration results for each signal processing circuit in the controller in advance, the individual signal processing circuits and the controller that functions as a reading device that reads information from these circuits are different. Signal processing circuits that are inseparable from each other and whose calibration results are not stored in the controller cannot be used with the controller. That is, a data collection device cannot be configured by combining an arbitrary signal processing circuit and an arbitrary controller.

Third, this data acquisition device processes the outputs of multiple signal processing circuits with one controller. The output of each signal processing circuit is stored in the controller for each signal processing circuit. It is necessary to correct by the controller based on the calibration result of. Therefore, as the number of signal processing circuits increases, the load on the controller becomes enormous, and the number of signal processing circuits that can be handled by one controller is limited. Disclosure of the invention

An object of the present invention is to provide a sensor device capable of performing accurate measurement even when a sensor device is combined with a readout device not previously associated with the sensor device.

Another object of the present invention is to provide a setting device for setting a sensor device, a reading device for reading information from the sensor device, and an article management system for managing articles using the sensor device, the setting device, and the reading device. To provide effective use of the sensor device.

In order to achieve the above object, a sensor device according to one aspect of the present invention includes a sensing circuit having a sensor element mounted thereon, a coil for receiving electromagnetic wave energy transmitted from an electromagnetic wave radiating means provided outside, and the coil A power supply unit that is connected to the power supply and generates an internal power supply; an information decoding unit that decodes information that is superimposed on the electromagnetic wave energy and includes an allowable value of a parameter detected by a sensing circuit; and a permission unit that is decoded by the information decoding unit. It is characterized by comprising: a nonvolatile memory for storing a value; and a transmitting unit for transmitting information based on the output of the sensing circuit to the outside.

In the sensor device of the present invention, the permissible value that enables the individual difference of the sensor device to be removed is stored in a state that can be read from the outside, so that the sensor device and the reading device not previously associated with the sensor device are stored. Accurate measurement can be performed by the combination.

For example, a parameter value is measured in advance under a predetermined condition using a sensor device having standard characteristics to determine a standard value (standard allowable value), and the output of the sensing circuit obtained under the same condition (standard allowable value) is obtained. Based on the (detected value) and the standard value, the allowable value is corrected by an external device or sensor device so that the deviation of the detected value from the standard value is equivalently removed. As a result, the allowable value suitable for a sensor device having standard characteristics is corrected to a value suitable for a sensor device having different characteristics. This correction is equivalent to calibrating the characteristics of the sensing circuit. If the correction of the tolerance is performed by an external device, In this case, the electromagnetic energy on which the corrected allowable value is superimposed is sent from the outside to the sensor device, where the allowable value is decoded and stored in the non-volatile memory. On the other hand, when the tolerance value is corrected by the sensor device, the standard tolerance value is sent from the outside to the sensor device, and the sensor device uses the sensor device based on the standard tolerance value and the output value of the sensing circuit. A device-specific tolerance is determined and stored in non-volatile memory.

According to the present invention, the output of the sensing circuit and the corrected tolerance included in the information read from the sensor device are generally the calibrated sensor output generated by the reading device and the tolerance stored in the reading device in the related art. Equivalent to the value. In other words, since the calibrated sensing circuit output is equivalently sent from the sensor device of the present invention, it is not necessary to calibrate the output of the sensing circuit with the reading device. In other words, even when information is read from the sensor device using a readout device that is not previously associated with the sensor device, the individual differences of the sensor device are compared before the output of the sensing circuit based on the information and the allowable value are compared. Has been removed in advance, so that the comparison between the two can be performed accurately, in other words, an accurate measured value can be obtained. Therefore, it is not essential to use the sensor device and the reading device in pairs. For example, when mass-producing a data collection device including a signal processing circuit having a sensor device and a controller having an information reading function, assembling individual data collection devices using an arbitrary signal processing circuit and an arbitrary controller. Can be.

In the present invention, preferably, the sensor device includes an output comparing unit that compares an output of the sensing circuit with an allowable value.

According to this preferred aspect, since the sensor device itself can determine whether or not the output of the sensing circuit is out of the allowable range represented by the allowable value, there is no need to provide a determination device on the reading device side.

Preferably, the output comparison unit stores the result of the comparison in a nonvolatile memory. According to this preferred aspect, the comparison result can be stored in the non-volatile memory and read later. Therefore, unlike the related art in which the output of the sensor device is always read by the reading device during the measurement and compared with the allowable value, in this preferred embodiment, it is not essential to read the output of the sensing circuit during the measurement. No need to install at measurement site. The electromagnetic radiation means (energy supply device) will be used to generate power in the sensor device, but the simplicity of measurement will not be impaired. Preferably, the sensor device includes a resonance circuit including a coil, and means for switching a resonance frequency of the resonance circuit according to a comparison result of the output comparison unit. According to this preferred aspect, the sensor device changes the resonance frequency in accordance with the comparison result between the output of the sensing circuit and the allowable value, so that the reading device can know the comparison result instantaneously only by examining the resonance frequency. Can be.

According to another aspect of the present invention, there is provided a setting device, wherein the setting device includes: a receiving unit that receives information from a sensor device; and a receiving unit that receives the information from the sensor device placed in a predetermined environment. It is characterized by comprising setting means for setting an allowable value of a parameter detected by the sensing circuit of the sensor device based on the information, and transmitting means for radiating electromagnetic energy with the information superimposed.

According to the setting device of the present invention, when the information indicating the output of the sensor device under the predetermined environment is transmitted from the transmitting unit of the sensor device, the receiving means receives this information and sends it to the setting means. In the setting means, a standard value (standard allowable value) representing the output of a sensor device having standard characteristics when the sensor device is placed in a predetermined environment can be stored in advance. In this case, the setting means sets an allowable value unique to each sensor device based on the standard value and the detected value (information received by the receiving means). The transmitting means emits an electromagnetic wave energy on which information indicating the allowable value set by the setting means is superimposed. The sensor device decodes the allowable value from the electromagnetic wave energy and stores it in the nonvolatile memory. This tolerance is read when the sensor device is read out with the sensor device output. It is possible to remove individual differences in the location.

In this way, by using the setting device, it is possible to set an allowable value specific to each sensor device for each sensor device, and it is not necessary to calibrate the output of the sensor device on the reading device side. Therefore, accurate measurement can be performed even when an arbitrary sensor device and an arbitrary reading device are combined, and there is no need to use a specific sensor device and a specific reading device as a pair.

According to still another aspect of the present invention, there is provided a reading device, comprising: a transmitting device that emits electromagnetic wave energy to the sensor device; and a receiving device that receives information from the sensor device. It is characterized by having.

According to the reading device of the present invention, it is possible to radiate electromagnetic wave energy from the transmitting unit to drive the sensor device, and then to receive information from the sensor device by the receiving unit. The information from the sensor device includes the output of the sensor device and an allowable value capable of eliminating individual differences between the sensor devices, and there is no need to calibrate the output of the sensor device on the reading device side. Therefore, accurate measurement can be performed based on information read from the sensor device using an arbitrary reading device.

According to still another aspect of the present invention, there is provided an article management system including the above-described sensor device mounted on an article, the above-mentioned setting apparatus, and the above-mentioned reading apparatus. In the article management system according to the present invention, for example, a permissible value unique to each sensor device is set in advance using a setting device for each of the sensor devices mounted on each of a large number of movable articles, and the measurement environment Below, for example, during storage or transport of goods, measurements are taken by individual sensor devices and the measurement results are stored. After the storage or transportation of the goods, the reading device reads the measurement results from the sensor device, and based on the measurement results, determines whether or not the management state of each article during storage or transportation of the goods is good. . According to the present invention, accurate measurement can be performed even when an arbitrary sensor device, an arbitrary setting device, and an arbitrary reading device are used in combination. Can be constructed flexibly and easily. The article management system of the present invention is particularly useful for quality control of moving articles, and for example, can suitably control freshness of fresh foods transported from a production area to a market. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic block diagram showing a sensor device and a setting and reading device according to a first embodiment of the present invention,

FIG. 2A is a diagram showing an example of a coil used in the sensor device shown in FIG. 1, FIG. 2B is a schematic perspective view showing another example of the coil,

FIG. 2C is a schematic perspective view showing still another example of the coil;

FIG. 3 is a diagram showing a configuration example of a power supply unit of the sensor device shown in FIG. 1, FIG. 4 is a diagram showing a configuration example of a sensing circuit of the sensor device shown in FIG. 1, FIG. Is a schematic block diagram showing a sensor device and a setting and reading device according to a second embodiment of the present invention,

FIG. 6 is a schematic perspective view showing an article management system according to a third embodiment of the present invention, FIG. 7 is a schematic block diagram of an article management system according to a fourth embodiment of the present invention, and FIG. FIG. 7 is a diagram showing the resonance circuit setting unit shown in FIG.

FIG. 9 is a diagram showing a temperature measuring system according to a fifth embodiment of the present invention,

FIG. 10 is a diagram showing a fluid measurement system according to a sixth embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a sensor device and a setting / reading device according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4.

As shown in FIG. 1, the setting device (parent device) 1 includes a transmitting means 11, a receiving means 12 and an allowable value setting means 13 and functions as a reading device. 01 04413

(Hereinafter, setting device 1 may be referred to as reading device 1). The sensor device (slave unit) 2 includes a coil 20, a power supply unit 21, an information decoding unit 22, a nonvolatile memory 23, a sensing circuit 24, and a transmission unit 25. Reference numeral 3 indicates a communication space between the setting device 1 and the sensor device 2.

The sensor device 2 can be provided at low cost by being integrated as a one-chip IC using a semiconductor such as CMOS. In this case, the sensing circuit 24 equipped with a sensor element such as a temperature sensor element is also made of CMOS, but the characteristics of the sensing circuit created by the CMOS process have individual differences. Values often vary by tens of percent.

Calibration is performed to eliminate such measurement errors due to individual differences in the sensing circuit. In general, when a sensor device having standard characteristics (a sensor device of the same type as or different from the sensor device to be calibrated) is placed in a predetermined environment, the output value output from the sensor device is set in advance as a reference value. The output value of the latter sensor device is calibrated based on the comparison result between the reference value and the output value from the sensor device having individual differences under a predetermined environment. Specifically, in the case of a sensor device equipped with a temperature sensor element, the temperature data output from the sensing circuit of the sensor device under the measurement environment is compared with a reference temperature value obtained in advance using a standard sensor device. Calibration is performed by comparison. In the case of a sensor device having a pressure-sensitive element, the measured pressure value of a sensor device having individual differences is calibrated based on a reference pressure value obtained in advance using a standard sensor device. With respect to other sensor devices having a sensor element, an appropriate environment can be prepared to obtain a reference value, and the same calibration is performed. Then, a comparison result between the calibrated output value and a preset allowable value is provided to various controls.

Although the above calibration is performed in a broad sense also in the present embodiment, the setting device 1 and the sensor device 2 of the present embodiment It is characterized by calibrating the value.

At the time of this calibration, a sensor device 2 having individual differences is placed in a predetermined environment, for example, in a thermostat. Then, after the sensing circuit 24 of the sensor device 2 is stabilized under a predetermined environment, the setting device 1 radiates electromagnetic wave energy from the transmission means 11 to the communication space 3. When the circuit configuration of the setting device 1 is simplified, or in the case of a sensor device in which an antenna for receiving electromagnetic wave energy is composed of a coil, a short wave of several hundred kHz to tens of MHz is used as electromagnetic wave energy. Is appropriate, but not limited to this. The setting device 1 amplifies a high-frequency signal generated by an oscillator (not shown) in the transmitting means 11 and radiates it as electromagnetic wave energy to the communication space 3 via an antenna.

This electromagnetic wave energy is taken into the sensor device 2 via the coil 20. The coil 20 may be formed by winding a copper wire in a loop shape, but may be formed on a semiconductor chip in order to reduce the size of the sensor device 2. FIG. 2A shows a coil 20 obtained by winding a copper wire a plurality of times in a loop, and FIG. 2B shows a coil 20 made of a conductor formed on the surface of a semiconductor chip 4 by photolithography. Further, when the sensor device 2 is realized using a spherical semiconductor having a diameter of several mm, the coil 20 is formed on the spherical surface of the spherical semiconductor 5 as shown in FIG. 2C. Consists of conductors. As shown in Fig. 2C, a sensor device composed of a spherical semiconductor can be easily mounted on an object such as an article, and can be easily embedded inside the object with a syringe.

The electromagnetic wave energy taken from the coil 20 is converted from alternating current to direct current by the power supply unit 21 to generate an internal power supply. Fig. 3 shows an example of the power supply unit 21. Both ends of the coil 20 are connected to a full-wave rectifier circuit 31, which converts electromagnetic energy from AC to DC. The limiter 32 is constituted by a zener diode in the illustrated example. For example, the communication distance between the sensor device 2 and the setting device 1 is short. Also in this case, an overvoltage of several tens of volts or more is prevented from being generated at both ends of the coil 20, and the element in the sensor device 2 is prevented from being broken due to the overvoltage. The electromagnetic wave energy converted into direct current by the full-wave rectifier circuit 31 is supplied to the legged filter 33 under overvoltage protection by the limiter 32. The regulator generates a predetermined voltage between VCC (power supply line) and GND (ground line), and supplies it to each circuit of the sensor device 2 as power. In this example, a full-wave rectification circuit is shown as achieving the rectification function, but a half-wave rectification circuit may be used. In addition, the limiter 32 is not limited to a zener diode as long as it has a similar overvoltage protection effect, such as a shunt regille night.

When the internal power generated by the power supply unit 21 is supplied to each circuit of the sensor device 2, the sensor device 2 becomes operable. The sensing circuit 24 includes, for example, a ring oscillator or the like having a temperature-sensitive element, and starts oscillating when it becomes operable. Fig. 4 shows a configuration example of the sensing circuit 24. The sensing circuit 24 includes a ring oscillator 41 composed of a resistor 42, a capacitor 43 and a plurality of inverters 44, a counter 45 for measuring the oscillation frequency of the ring oscillator 41, and a ring oscillator 45. It consists of a latch 46 that holds the count value of the counter 45 that indicates the oscillation frequency of 41 at a predetermined timing. The resistance 4 and the capacitance 43 are temperature-sensitive elements, and the values (resistance and capacitance) of both elements change according to the change of the ambient temperature, and the oscillation frequency of the ring oscillator 41 changes. The output of the ring oscillator 41 is input to the counter 45, and the counter 45 measures the oscillation frequency of the ring oscillator 41. That is, the sensing circuit 24 is provided with a temperature sensor element to perform temperature measurement.

When measuring the oscillation frequency of the ring oscillator 41, the electromagnetic wave energy or the output of the ring oscillator 41 is shaped by, for example, a waveform shaping circuit (not shown) to obtain a clock signal, while a pulse is generated in the counter 45. Let the example of the clock signal For example, the number of pulses generated within one generation cycle is counted at count 45. If an oscillator such as a crystal oscillator or an oscillation circuit such as a ring oscillator is separately mounted on the sensor device 2, the waveform shaping circuit is unnecessary. The count value of the counter 45 is held in the latch 46 at a predetermined timing, and the count value is transmitted to the transmission unit 25.

As described above, the temperature measurement for calibration is performed by the sensor device 2 placed in a predetermined environment. For example, the known setting degree of the thermostatic chamber is measured by the sensor device 2, and the set temperature is compared with the measured temperature.

Specifically, the sensor device 2 transmits to the setting device 1 a measured value corresponding to the known set temperature, that is, an output value (measured temperature data) of the sensing circuit 24. Specifically, when the setting device 1 superimposes the measurement command signal on the electromagnetic wave energy and transmits it to the sensor device 2 and requests the sensor device 2 to return the output of the sensing circuit 24, the sensor device 2 The information decoding unit 22 decodes the measurement command signal, and then returns the output value of the sensing circuit. Alternatively, the sensor device 2 may be set in advance so that the output of the sensing circuit 24 is returned when an unmodulated wave is received. In this case, the setting device 1 converts the unmodulated electromagnetic wave energy Just send it.

When transmitting the measured temperature data, the transmission unit 25 of the sensor device 2 encodes the data, such as a bi-phase code, Manchester encoding, and transmits the encoded data to the setting device 1 via the coil 20. Send. As a transmission method, for example, a method that changes a small magnetic field by changing the impedance of the sensor device 2 or a method of transmitting a radio wave can be considered, but a method of transmitting data to the setting device 1 in a contactless manner is considered. If so, it is not limited to this.

The setting device 1 receives the measured temperature data returned from the sensor device 2 by the receiving means 12 and amplifies or demodulates the received data to restore the measured temperature data from the sensor device 2 and converts the received data into an allowable value setting means. Transmit to 13 Allowable value setting means 13 The measured value of the standard sensor device below is held as reference value data, and calibration is performed to match the measured temperature data transmitted from the sensor device 2 with the reference value data.

As described above, the temperature measurement for calibration is performed by the sensor device 2, and then the calibration is performed by the setting device 1 based on the measured temperature data transmitted from the sensor device 2. Hereinafter, a specific example of the procedure will be described.

First, first, second, and third thermostatic chambers capable of setting the first, second, and third set temperatures (for example, 15 degrees Celsius, 25 degrees Celsius, and 35 degrees Celsius) are prepared. The sensor device 2 is placed in the first constant temperature bath. After the temperature of the sensor device 2 is stabilized at 15 degrees Celsius, the measurement command signal is transmitted from the setting device 1 to the sensor device 2. In response, the sensor device 2 returns the first measured output value a (not shown) to the setting device 1. The setting device 1 stores the first set temperature and the first measured output value a as a set. Next, the sensor device 2 is placed in the second constant temperature bath, and the same operation as above is performed. The setting device 1 is set to the second set temperature and the second measured output value b (not shown). Remember. Further, the sensor device 2 is put into the third constant temperature bath, and the same operation is performed. Then, the third set temperature and the third measured output value c (not shown) are stored in the setting device 1 as a set and stored. Let it. The setting device 1 obtains and stores a temperature output characteristic curve passing through three points (15 degrees, a), (25 degrees, b), and (35 degrees, c). Instead of the three thermostats, it is also possible to use one thermostat that can be sequentially set to the first, second and third set temperatures. In addition, although the accuracy increases as the number of measurement points increases, the amount of work also increases.

Next, after taking out the sensor device 2 from the constant temperature bath, an allowable value setting operation is performed for the sensor device 2. Here, the permissible value is, for example, the upper limit value, the lower limit value, or the upper and lower limit value of the permissible temperature range in which the freshness of the food is maintained, and if the storage environment temperature of the food exceeds the permissible value, the freshness of the food is adversely affected. Will be reached. Sensor device 2 is a variety of articles For example, it can be attached to fruits and frozen foods, and the permissible value (upper limit) may be set to, for example, 20 degrees Celsius for fruits and to, for example, -5 degrees Celsius for frozen foods.

In relation to the tolerance, in the conventional method, the output value from the sensor device is calibrated based on the deviation between the output value of the sensor device at a set temperature and the output value of the standard sensor device, and is compared with the tolerance value However, this allowable value is obtained from the temperature output characteristic curve of a sensor device having standard characteristics, and is used in common for each sensor device. On the other hand, in the present embodiment, an allowable value unique to each sensor device is set based on the temperature output characteristic curve of each sensor device. In other words, in the present embodiment, instead of calibrating the output value of the sensor device, a standard allowable value is calibrated to an allowable value suitable for each sensor device.

Specifically, when setting an allowable value, when an operator inputs, for example, 20 degrees as a set value to the allowable value setting means 13 of the setting device 1, the setting device 1 receives the sensor stored in advance. The measured output value d of the sensor device 2 at 20 degrees is calculated from the temperature output characteristic curve of the device 2. In the sensor device 2, the measurement temperature is represented by the count value of the counter 45 of the sensing circuit as described above. Therefore, the setting device 1 calculates the count value corresponding to the measurement output value d as the measurement output value d. Set the count value as an allowable value. As described above, the allowable value is set based on the temperature output characteristic curve of the sensor device 2, and becomes a value unique to the sensor device 2.

In the setting device 1, the allowable value set by the allowable value setting means 13 is supplied to the transmitting means 11, and the transmitting means 11 transmits the allowable value (the electromagnetic wave on which the allowable value data including the measured output value is superimposed). The energy is radiated toward the sensor device 2. Specifically, in order to superimpose the allowable value data on the electromagnetic wave energy, the high-frequency signal as the electromagnetic wave energy is modulated at a permissible value. ASK (Am 1 itude S ift K eying) or FSK (Fre Q uency S hift K e ying), but not limited to this. In addition, information indicating whether the allowable value is the upper limit value or the lower limit value is added to the allowable value data.

In the sensor device 2, when the electromagnetic wave energy is received by the coil 20, the internal power is generated in the power supply unit 21 and the circuit in the sensor device 2 becomes operable. The information decoding unit 22 demodulates the electromagnetic energy (modulated high-frequency signal) on which the allowable value data set by the setting device 1 is superimposed, and decodes the allowable value from the high-frequency signal. The allowable value is stored in the nonvolatile memory 23.

The sensor device 2 generates internal power from electromagnetic energy, and is used when the setting device 1 is not installed or when the sensor device 2 is located in a place where electromagnetic energy cannot be received from the setting device 1. Cannot generate internal power. Therefore, it is desirable to configure the memory of the sensor device 2 as a non-volatile memory that retains the stored contents even without power. In addition, the allowable value stored in the memory is compared with the output value of the sensing circuit 24 in the temperature measurement performed after setting the allowable value, so that the memory can write the allowable value only once, and thereafter, It is desirable to use a fuse type so that writing is not mistakenly performed, but it is also possible to use an EEPROM that can be electrically rewritten multiple times, such as an EEPROM.

In the above description, the setting operation of the allowable value is performed after the sensor device 2 is taken out of the constant temperature bath, but the present invention is not limited to this. Taking the above case as an example, if the calibration work is completed with the sensor device 2 placed in a 35 ° C constant-temperature bath and the work of setting the allowable value is then performed, the work efficiency will be high. Become. However, in this case, if the allowable value is set to 35 degrees, which is the same as the ambient temperature, the sensor device 2 may malfunction, so it is better to avoid this.

In the above example, the temperature output characteristic curve obtained from the measurement data for a plurality of temperature measurement points is stored in the setting device 1. However, instead of this, the setting value (for example, 2 0 degree) into the constant temperature bath set at a temperature equal to The measurement may be performed only at this set temperature, and the measured value may be set as an allowable value. In this case, after removing the sensor device 2 from the constant temperature bath, the allowable value is transmitted to the sensor device 2 and stored in the nonvolatile memory 23. As described above, the setting of the allowable value can be performed by a method according to the temperature management requirements of the system to which the sensor device is applied.

After the permissible value is stored in the non-volatile memory 23, the sensor device 2 is mounted on, for example, an appropriate article, placed in a measurement environment, and used for measuring the ambient temperature of the article. In this temperature measurement, the sensor device 2 is used together with a setting device 1 (hereinafter, referred to as a reading device 1 or a setting 'reading device 1) having a function as a reading device, and the sensor device 2 is provided with a measurement value (sensing device). The output value is output to the reading device 1 together with the output value of the circuit. Unlike the conventional method, in the present embodiment, it is not necessary to calibrate the output of the sensor device 2 on the reading device 1 side, and therefore, the temperature output characteristic curve data of the sensor device 2 for which the setting of the allowable value has been completed. It is not necessary to keep evening in reading device 1. In other words, in the measurement environment, the sensor device 2 can be used not only with the setting reading device 1 used for setting the allowable value but also with other reading devices.

Specifically, in the measurement environment, the readout device 1 radiates electromagnetic energy from the transmission means 11 to the sensor device 2. A command for reading data from the sensor device 2 is added to the electromagnetic wave energy. Alternatively, as described above, the sensor device 2 may be set in advance so as to transmit data when unmodulated electromagnetic wave energy is received. The sensor device 2 receives the electromagnetic wave energy with the coil, generates an internal power supply in the power supply unit 21, and becomes operable. When operation becomes possible, the output value is transmitted from the sensing circuit 24 to the transmission unit 25, and is transmitted from the transmission unit 25 to the outside. Subsequently, the permissible value stored under the predetermined environment is read out from the nonvolatile memory 23, transmitted to the transmission unit 25, and transmitted to the outside similarly. However, output The order of transmitting the value data and the allowable value data is not limited to this.

The readout device 1 receives the output value and the permissible value data of the sensing circuit 24 transmitted from the sensor device 2, performs demodulation and amplification, and compares the output value of the sensing circuit 24 with the permissible value. For example, the output value data includes the count value of the sensing circuit 24 in the measurement environment, and the allowable value data includes the sensing circuit 24 at the set temperature (for example, 20 degrees Celsius) related to the setting of the allowable value. Count value (hereinafter referred to as an allowable value or a count value indicating an allowable value), and a command indicating that the allowable value is the upper limit value. In this case, the reading device 1 compares the count value of the sensing circuit 24 in the measurement environment with the count value representing the permissible value, and determines whether the output value exceeds the permissible value. If the output value of the sensing circuit 24 exceeds the allowable value, the readout device 1 recognizes that the ambient temperature of the sensor device 2 has exceeded the set temperature, and updates the history record with the time at that time. . Further, if the reading device 1 has a function of an air conditioner, the reading device 1 starts a temperature control operation. Alternatively, the air conditioner connected to the reading device 1 starts the temperature control operation.

Thereafter, the sensor device 2 may constantly transmit the output value of the sensing circuit, or may transmit a command from the reading device 1 at predetermined intervals to read the output value of the sensing circuit. When the output of the sensing circuit 24 of the sensor device 2 falls within the allowable range again due to the temperature control operation of the reading device 1, the reading device 1 returns the measurement temperature to the allowable range by a reply from the sensor device 2. Recognizes that the temperature has been stored inside and stops the temperature control operation.

The allowable number of times that the temperature of the article or its surroundings exceeds the upper or lower limit temperature changes depending on the durability of the article to the temperature, but the comparison between the output value data from the sensor device 2 and the allowable value data is repeated. By using this, you can know how many times the temperature of the article and its surroundings has deviated from the allowable range. Is effective in Also, when the sensor device 2 is mounted on an article that cannot exceed the allowable value even once, the readout device 1 receives the reply data from the sensor device 2 after the output value exceeds the allowable value. It may be ignored or the operation of the sensor device may be stopped by a command.

As described above, the setting device 1 sets an allowable value based on the output value of the sensing circuit of the sensor device 2 in a predetermined environment, and transmits the electromagnetic wave energy with the allowable value superimposed thereon. Since the permissible value is decoded from the energy and stored in the non-volatile memory, each sensor device can have its own permissible value calibrated to the sensing circuit. After the allowable value is set for each sensor device, the reading device 1 monitors whether the temperature detected by the sensor device is outside the set temperature range by reading the allowable value and the output value of the sensing circuit and comparing them. This eliminates the need to pair the readout device 1 and the sensor device 2, and does not impose a burden on the readout device to hold the calibration data and allowable value data of each sensor device. Note that a plurality of allowable values can be set. For example, in the above-described example, it is also possible to set 15 degrees, 20 degrees, 30 degrees, and the like, and compare them stepwise.

Hereinafter, a sensor device and a setting / reading device according to the second embodiment of the present invention will be described with reference to FIG.

The sensor device and the setting / readout device of the present embodiment perform such a comparison with the sensor device and compare the result of the comparison with the first embodiment in which the output value of the sensing circuit and the allowable value are compared by the readout device. The difference is that the data is transmitted from the sensor device to the reading device, and the other points are the same as those of the first embodiment.

That is, the setting / reading device of the present embodiment has the function of the setting device and the function of the reading device (hereinafter, the setting / reading device may be referred to as the setting device or the reading device). The sensor device 2 is a sensor with a temperature sensor element. And an output comparing section 26 for comparing the output value of the sensing circuit 24 with an allowable value.

The setting of the allowable value for the sensor device 2 is performed in the same manner as in the first embodiment. Simply put, the temperature output characteristic curve of the sensor device 2 is obtained based on the output value transmitted from the sensor device 2 placed in the constant temperature bath and the set temperature of the constant temperature bath, and the allowable value is obtained from the characteristic curve. Is written to the nonvolatile memory 23. After the writing of the allowable value is completed, the sensor device 2 is mounted on the article and placed under the measurement environment.

In the measurement environment, the sensor device 2 captures the electromagnetic wave energy from the readout device 1 through the coil 20 and generates an internal power supply from the electromagnetic wave energy in the power supply unit 21. Start temperature measurement by sensing circuit 24. The output comparing section 26 reads the allowable value from the nonvolatile memory 23 and compares it with the output value of the sensing circuit 24.

Since a permissible value to be compared with the output value is held in the sensor device 2 in advance, there is no need to transmit the permissible value from the reading device 1 to the sensor device 2, and therefore, the electromagnetic wave energy radiated by the reading device 1 Does not need to be a modulated wave modulated with information indicating an allowable value, and may be an unmodulated wave. In the case of an unmodulated wave, the electromagnetic wave energy does not include a command for performing comparison execution, but the comparison between the output value and the allowable value is performed by the latch value 46 of the sensing circuit 24 and the count value (corresponding to the output value). May be performed in accordance with the timing at which is held. Such a comparison can be always performed, for example, within a period in which an internal power supply can be generated from electromagnetic wave energy transmitted from the reading device 1. On the other hand, when the electromagnetic wave energy on which the command indicating the comparison execution timing is superimposed is used, the output comparison unit 26 of the sensor device 2 compares the output value with the allowable value when receiving such a command. I do. Such a command can be transmitted multiple times as needed during the period in which the internal power supply can be generated. In this case, the comparison is performed each time a command is received. The output comparing section 26 determines whether or not the output value of the sensing circuit 24 has exceeded an allowable value, and transmits the determination result to the transmitting section 25. The transmission unit 25 transmits the determination result to the reading device 1 via the coil 20. The reading device 1 checks whether the temperature (output value) measured by the sensor device 2 has exceeded the set temperature (permissible value) based on the comparison result received from the sensor device 2, and makes a judgment at each judgment time. Update history records. More simply, the output comparison unit 26 can transmit only the determination result that the output value has exceeded the allowable value to the transmission unit 25, and in this case, the measurement is stored in the non-volatile memory 23 of the sensor device 2. Record the time when the temperature exceeded the set temperature and the period during which the measured temperature exceeded the set temperature. In connection with the history recording, for example, a counter that measures the elapsed time from the start of reception of electromagnetic wave energy from the reading device 1 is provided in the sensor device 2.

If the output of the sensing circuit 24 of the sensor device 2 is unstable and may fluctuate near the allowable value, the determination means of the output comparison unit 26 should be provided with hysteresis to perform stable comparison. Is also conceivable. When the allowable value is stored in the non-volatile memory 23 of the sensor device 2, the device number unique to the sensor device 2 is transmitted from the setting device 1 to the sensor device 2, and the device number is stored in the memory 2 3 together with the allowable value. In this case, the device number can be transmitted from the sensor device 2 to the reading device 1 together with the result of the comparison between the output value and the allowable value. It can be determined whether the reply is a reply.

Hereinafter, an article management system according to a third embodiment of the present invention will be described with reference to FIG.

In recent years, strict quality control is required for articles, especially foods such as fruits. For example, foods transported by air or boat for long periods of time may lose their freshness and become spoiled if they are not stored within acceptable temperature ranges during transport. Therefore, the temperature of various foods is measured during transportation, and the products that can be stored within the allowable temperature range and those that cannot be stored are sorted after transportation based on the temperature measurement results. It is desirable.

The article management system according to the present embodiment meets such a demand, and includes a setting / readout device and a large number of sensor devices having the same basic configuration as those of the second embodiment. Although the sensor device can be attached to various articles, a case where the sensor device is embedded in a central portion of a fruit such as an apple will be described in the present embodiment. In FIG. 6, reference numeral 50 denotes fruit as an article, which is transported in a container 51. The container 51 is provided with an electromagnetic wave energy supply device (corresponding to a setting and reading device or a reading device) 1A.

The sensor device of the present embodiment is similar to the sensor device of the second embodiment (see FIG. 5), and has a sensing circuit 24 having a temperature sensor element and a non-volatile memory storing an allowable value unique to each sensor device. 23, the determination result that the output value of the sensing circuit 24 has exceeded the allowable value in the measurement environment during transportation is written in the non-volatile memory 23. Management can be easily performed at the sorting stage. The determination result data written to the nonvolatile memory 23 includes, for example, information indicating whether the allowable value is the upper limit value or the lower limit value, and the time when the output value exceeds the allowable value. The sensor device 2 of the present embodiment is formed by coating a spherical integrated circuit device having a diameter of 1 mm with an insulating layer (protective layer), and is easily embedded in the center of the fruit 50 with a syringe or the like. It is possible. In other words, a spherical sensor device can be obtained by simply coating the spherical integrated circuit device with an insulating layer, and the coated sensor device is suitable for embedding into an object because it has no corners. In addition, this sensor device is superior to a case where a flat IC chip is coated in a spherical shape in terms of labor and the strength of the integrated circuit device. The insulating layer is made of a resin material that is not corroded by acidic juice and does not cause any serious food hygiene problems.

The embedding of the sensor device 2 into the fruit 50 may be performed during the fruit growth process. In the case of citrus fruits, the sensor device can be embedded in the skin of the fruits. As a simpler method, there is a method of attaching the sensor device 2 to the fruit 50 with an adhesive tape or the like. That is, a circular sheet piece having a diameter of about 20 millimeters is obtained from an adhesive sheet having an adhesive material layer on the back surface, and the sensor device 2 is disposed at the center thereof. Then, the sheet piece is adhered to the surface of the fruit 50. The material and thickness of the sheet were selected so that the sensor device 2 did not fall off during use and did not drop off, and did not completely block the electromagnetic wave energy sent to the sensor device 2 and had no food hygiene problems. Select. In addition, appropriate color, pattern, trademark, etc. shall be attached to the sheet pieces so that consumers will not accidentally eat them, so that they can be easily discerned by the naked eye. The sensor device 2 has a spherical shape with a diameter of about 1 millimeter, so when it is attached to the surface of the fruit 50, the surface force of the sheet piece S is slightly raised, and even if the fruits 50 rub during transportation The fruit 50 is hardly damaged by the device 2, but if the fruit 50 is an apple or the like, a sheet piece should be attached so that the sensor device 2 fits into one of the upper and lower depressions. good. Alternatively, it is even better to attach a sheet piece so that the sensor device 2 is located in a portion where there is no problem even if it is damaged, such as in the evening.

As described above, each sensor device 2 stores, in the nonvolatile memory 23, a unique permissible value capable of eliminating the influence of manufacturing variations of the sensing circuit. All sensor devices housed in the container 51 receive the electromagnetic wave energy from the energy supply device (corresponding to the setting device or the reading device) 1 A, and are always operable. Compares the value with the permissible value and writes the comparison result to the nonvolatile memory.

Then, after transportation, each of the fruits (articles) 50 taken out of the container 51 is inspected for quality. In the inspection, as the belt conveyor 52 moved, the fruits 50 moved to the readout device 1 B installed in the sorting work area Then, when passing through the reading device IB, the information stored in the nonvolatile memory 23 of each sensor device 2 is read by the reading device 1B. When the output value of the sensing circuit 24 exceeds the allowable value, information indicating that fact is written in the nonvolatile memory 23, and the reading device 1B stores such information. Nothing is notified to the sorter 53, and the sorter 53 sorts the fruit 50 into a good product and a defective product.

In Fig. 6, fruit 50B is out of the permissible temperature range and its quality cannot be guaranteed, and it is judged as defective by the sorter 53, while fruit 5OA is stored within the permissible temperature range. It was sorted out as good.

By attaching or embedding the sensor device 2 in each article in this way, when the temperature of the article is out of the allowable temperature range, the fact is stored as a history, and the articles are sorted based on this history. Thereby, it is possible to perform temperature control and sorting of articles for each individual article. Furthermore, since the information can be collected in a non-contact manner, the wiring conventionally used for connecting the sensor device and the reading device becomes unnecessary. Needless to say, the history obtained by comparing the output value with the allowable value a plurality of times as described above can be written to the nonvolatile memory. Further, a plurality of allowable values may be set in stages.

Hereinafter, an article management system according to a fourth embodiment of the present invention will be described with reference to FIGS. 7 and 8.

The article management system according to the present embodiment enables the reading device to easily determine whether or not the output value of the sensor device attached to each article is out of the allowable range even at least once. Is further simplified.

In the sensor device 2 of this embodiment, the permissible value transmitted from the setting device 1 is stored in the non-volatile memory 23, and the output value of the sensing circuit 24 and the permissible value are compared by the output comparing unit 26. The comparison is the same as that of the second embodiment, but the resonance circuit setting unit 27 is different from that of the second embodiment.

That is, when the output value of the sensing circuit 24 exceeds the allowable value, the output comparison unit 26 notifies the resonance circuit setting unit 27 of the fact. As shown in FIG. 8, the resonance circuit setting section 27 includes a variable capacitor 61 and a setting section 62 for setting a capacitance value of the capacitor 61, and includes a coil 20 and an output comparing section 2 6 and connected to. When setting the allowable value for the sensor device 2, the resonance frequency of the resonance circuit composed of the coil 20 and the variable capacitor 61 is determined by the frequency of the high-frequency signal (electromagnetic wave energy) supplied from the setting device 1. (Hereinafter, referred to as a first resonance frequency value), it is possible to increase the reception efficiency and generate a power supply sufficient for operating each circuit of the sensor device 2.

Then, a control signal indicating that the output value of the sensing circuit 24 has exceeded the allowable value is sent from the output comparison unit 26 of the sensor device 2 arranged in the measurement environment to the setting unit 62 of the resonance circuit setting unit 27. When transmitted, the setting unit 62 changes the capacitance value of the variable capacity unit 61, and the readout device 1 transmits the resonance frequency of the resonance circuit composed of the coil 20 and the variable capacity unit 61. Set to a value that is far from the resonance frequency of electromagnetic wave energy (hereinafter referred to as the second resonance frequency value).

As described above, when the resonance frequency is switched from the first resonance frequency value to the second resonance frequency value, the sensor device 2 decreases its electromagnetic wave energy reception efficiency and generates an internal power supply by the power supply unit 21. Will not be able to operate. Therefore, the setting unit 62 is provided with a fuse-type non-volatile memory capable of maintaining the information indicating the capacitance value of the capacitor 61, that is, the set value of the resonance frequency even when the internal power supply of the sensor device 2 is extinguished. Can be Alternatively, the non-volatile memory 23 can be used as such a memory.

In the sorting operation for the individual articles, the electromagnetic wave energy supply device 1B disposed in front of the sorter 53 is a high-frequency device having a frequency equal to the second resonance frequency value. Emits a signal. On the other hand, the non-volatile memory of the setting unit 62 of the sensor device in which the output value of the sensing circuit 24 exceeds the allowable value stores the high-frequency signal of the second resonance frequency value when the high-frequency signal of the second resonance frequency value is received. The information that maximizes the electromagnetic wave energy reception efficiency is stored, and the sensor device whose output value does not exceed the allowable value maximizes the reception efficiency when receiving the high-frequency signal of the first resonance frequency value. Information is stored.

Therefore, among the sensor devices that have reached the vicinity of the energy supply device 1B, only those whose output value of the sensing circuit 24 has exceeded the allowable value can operate by the high-frequency signal transmitted by the energy supply device 1B. Becomes That is, the energy supply device (readout device) 1B can determine whether the management state of the article to which each sensor device is attached is good or not.

The energy supply device 1B may detect the resonance frequency of the sensor device 2 by sweeping the frequency of the radiated high-frequency signal. The resonance frequency can be detected by examining the degree of coupling with the resonance circuit of the sensor device 2 and the like. With this method, it is possible to collect the detection results of the sensing circuits of each sensor device only by checking the resonance frequency of the sensor device 2.

Further, the readout device 1B may selectively make each sensor device 2 operable to send back data. Therefore, only the electromagnetic wave energy having one of the first and second frequency values is transmitted, and only the sensor device having the resonance circuit whose resonance frequency matches the frequency of the electromagnetic wave energy can be operated by increasing the power receiving efficiency. And let them reply back. Alternatively, a plurality of frequency signals having the first and second frequency values may be transmitted, and the individual sensor devices 2 may be operated to return data.

Hereinafter, a temperature measurement system according to a fifth embodiment of the present invention will be described with reference to FIG. When measuring the surface temperature of a rotating body such as a drill, it is impossible to connect a sensor element such as a resistance temperature detector and an electronic processing circuit with a cable or the like. It was difficult.

In addition, the injection molding machine used for resin molding melts and kneads the plastic resin material (raw material) charged from the inlet 91 into the screw 90, and then injects the resin material into the mold at high pressure. The screw 90 is maintained at a high temperature and is given rotation. Conventionally, in order to control the temperature of such a screw 90, the temperature of the screw 90 has been measured indirectly by a temperature sensor provided on the outer wall fixed outside the screw 90, It did not measure temperature. The temperature measurement system of the present embodiment is intended to measure the temperature of a rotating body, for example, a screw of an injection molding machine, and includes a sensor device and a reading device.

Specifically, as shown in FIG. 9, several sensor devices 2 are embedded in the screw 90. For this reason, when manufacturing the screw 90, a depression into which the sensor device 2 enters as shown in Fig. 2C is formed in the screw, and the sensor device 2 coated with an insulating layer etc. is inserted into the depression and fixed with adhesive or coagulant etc. I do. Then, the screw 90 to which the sensor device 2 is fixed is incorporated in the injection molding machine, and the reading device 1 is arranged outside the screw 90. The non-volatile memory of the sensor device 2 stores, as an allowable value, a molding temperature required for heating a thermoplastic material to impart plasticity.

During operation of the injection molding machine, the screw 90 melts the plastic resin at high temperature while rotating, but the temperature at that time is measured by the sensor device 2 and the temperature information and the allowable value are read out by the reading device 1 without contact. collect. The reading device 1 compares the temperature information (measured value) with the permissible value, and if the measured value exceeds the permissible value, sounds an alarm or sends a signal to control the injection molding machine to keep the molding temperature constant. To communicate. This allows the temperature of the screw 90 to be measured indirectly, instead of the temperature of the screw 90 itself. The temperature can be measured directly, and the adjustment of the molding temperature can be judged accurately.

Needless to say, the sensor device 2 may determine whether the measured value has exceeded the allowable value, and the reading device 1 may collect only the determination result. In addition, by recording the history of the temperature information of each sensor device mounted on the screw 90 for each injection molding cycle, it is possible to determine whether the durability of the screw 90 due to heat is reduced. . Further, the sensor device 2 equipped with the pressure-sensitive element may be installed at the injection part, and the injection pressure to the mold may be measured.

Hereinafter, a fluid measurement system according to a sixth embodiment of the present invention will be described with reference to FIG.

Conventionally, in order to measure the state of the fluid flowing inside the pipe 100, a measuring instrument that inserts a sensor into a predetermined portion of the pipe 100 may be used, but such a measuring instrument includes a fluid. There was a problem such as obstructing the flow of water. To measure the state of the inside of the tube 100 using radiation, expensive measuring equipment and specialized knowledge were required.

The fluid measurement system of the present embodiment includes the above-described sensor device 2 and the reading device. More specifically, as shown in FIG. 10, the sensor device 2 is coated with an insulating layer and put into a fluid, and moves along with the fluid in a tube 100. An allowable value is stored in the non-volatile memory of the sensor device. The sensor device 2 has a sensor element for detecting a state in a liquid, such as a sensor element for measuring a flow rate and a temperature sensor element. Further, the reading device 1 is installed around the tube 100, and an induced electromagnetic field is generated around the reading device 1 by electromagnetic wave energy radiated by the reading device. When the sensor device 2 arrives near the installation location of the reading device 1, the sensor device 2 receives the electromagnetic wave energy and becomes operable, measures the output data of the sensor element at that time, and transmits it together with the allowable value. The reading device 1 analyzes the state of the liquid in the tube 100 and the components in the liquid from the collected data, and Judge whether the condition is within the specified allowable range and control the liquid. Further, the comparison result between the output value of the sensor element and the allowable value may be stored in the nonvolatile memory of the sensor device 2. In that case, it is possible to collectively read the data from the memory at the exit of the pipe 100 and read it out from the memory with the device 1 to collectively grasp the state of the fluid in each part of the pipe 100. Become. Further, the electromagnetic wave energy may be constantly propagated in the tube 100 to generate an induced electromagnetic field, and the sensor device 2 may receive the electromagnetic wave energy anywhere in the tube 100. In that case, the sensor device 2 can always generate an internal power supply, and can operate the sensor elements at all parts in the tube 100 to collect data, and at regular intervals, or When an abnormality is found based on the comparison result between the output value and the allowable value, the occurrence of the abnormality may be stored in the nonvolatile memory. By mounting the sensor element according to the application on the sensor device 2, it is possible to grasp all the conditions in the pipe 100, such as the temperature distribution and flow rate change in the pipe 100, or the corroded part in the pipe 100. It becomes possible.

For example, the temperature sensor element can be constituted by a ring oscillator using a temperature sensing element as shown in FIG. 4, but is not limited to this as long as it converts a measured temperature into an electric signal. Further, a pressure-sensitive element for detecting pressure may be used. In that case, the pressure-sensitive element can be integrated on a single semiconductor together with the sensing circuit and the like. In addition, other sensor elements / sensing circuits can be similarly integrated. With either configuration, the history of the comparison result between the output value and the allowable value can be determined. Furthermore, instead of setting an allowable value on the reading device side, an allowable value indicating an allowable temperature range is set in the sensor device in advance, and based on the sensor output under a predetermined environment and the set allowable value, it is determined by itself. The function of changing the setting of the allowable value may be provided on the sensor device side, and the result information may be transmitted. This eliminates the need to provide a tolerance setting means on the reading device side.

Also, the sensor device processes based on the result measured by the sensing circuit. It goes without saying that the result of performing predetermined processing in the sensor device, such as the result of processing according to the command of the reading device and the like, can also be transmitted to the outside using the transmitting unit.

The present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention.

Claims

The scope of the claims

1. A sensing circuit equipped with a sensor element,

A coil that captures electromagnetic wave energy sent from electromagnetic wave radiation means provided outside;

A power supply unit connected to the coil to generate an internal power supply;

An information decryption unit that decrypts information including a permissible value of a parameter superimposed on the electromagnetic wave energy and detected by the sensing circuit;

A non-volatile memory that stores the permissible value decoded by the information decoding unit, and a transmission unit that transmits information based on an output of the sensing circuit to the outside.

A sensor device comprising:

2. The sensor device according to claim 1, further comprising an output comparing unit that compares an output of the sensing circuit with the allowable value.

3. The sensor device according to claim 2, wherein the output comparison unit stores a result of the comparison in a nonvolatile memory.

4. A resonance circuit comprising the coil, and means for switching a resonance frequency of the resonance circuit based on a result of the comparison in the output comparison unit. Item 7. The sensor device according to Item 1.

5. Receiving means for receiving information from the sensor device according to any one of claims 1 to 4,

Setting means for setting an allowable value of a parameter detected by a sensing circuit of the sensor device based on information received by the receiving device from the sensor device placed in a predetermined environment;

Transmitting means for radiating electromagnetic wave energy with information superimposed thereon;

A setting device comprising:

6. Charge the sensor device according to any one of claims 1 to 4 Transmitting means for emitting magnetic wave energy;

Receiving means for collecting information from the sensor device;

A reading device comprising:

7. The sensor device according to any one of claims 1 to 4 attached to an article,

A setting device according to claim 5,

A reading device according to claim 6;

An article management system comprising: